Copyleft does not mean fake-open-source, I'd not consider Linux fake-open-source for example. Though plenty of reason to use permissive licenses instead of copyleft and vice versa depending on your situation.

Copyleft is Free Software, free as in freedom. Pushover licenses (such as MIT) are working for free for Amazon, Google and Oracle. Which is fine if your boss is paying you money to work for free for Amazon, Google and Oracle - it's their money. If it's your own spare time, you might not like it as much.